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Photo: Wikimedia Commons, S. Shepherd

Now that summer is in full swing, most of us are spending more time outside. While we’re hiking through the woods, firing up the barbeque, or playing beach volleyball, it’s easy to overlook the active, varied world beneath our feet. Here are a few fun facts about dirt:

70,000 Different types of soil in the U.S.

1 Tablespoon of soil has more organisms in it than there are people on earth

500 Minimum years it takes to form one inch of topsoil

5,000 Different types of bacteria in one gram of soil

.01 Percent of the earth’s water held in soil

15 Tons of dry soil per acre that pass through one earthworm each year

1,400,000 Earthworms that can be found in an acre of cropland

20,000 Pounds of total living matter in the top six inches of an acre of soil

10 Percent of the world’s carbon dioxide emissions stored in soil

4,000 Gallons of water soil needs to produce one bushel of corn

11,000 Gallons of water soil needs to produce one bushel of wheat

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